Electrical sostenuto piano



June 23, 1931. s. COO-PER 1,811,077

ELECTRICAL SOSTENUTO PIANO Filed March 24, 1930 INVENTOR Patented June 23, 1931 PATENT OFFICE.

SI IMON COOPER, OF BROOKLYN, NEW YORK.

ELECTRICAL SOS'IENUTO PIANO Application filed March 24, 1930. Serial No. 488,466.

This invention relates to electrical sosteunto pianos, particularly of the type wherein electromagnetic means are employed for the sostenuto and these means are operated by -5, current pulsators directly connected to the strings. I The principal object of the present invention is to provide a method of and means for mounting a pulsator relative to a string or strings, whereby one of the electrodes of the pulsator may have dependable mechanical and preferably adjustablyv rigid connection with a desired partof a, string, a singing or non-singing part "thereof, during operation of the piano-with electrical sostenuto, and whereby whenever desired one or a plurality of the pulsators simultaneously may be readily disconnected to adapt the piano for ordinary playing.

The inventionwill be more clearly understood, and various other objects and the divers advantages thereof will be in part obvious and in part specifically pointed out hereinafter, in the course of the following description of a preferred one of the various possible forms of the invention as shown in the accompanying drawings;-it being understood, of course, that such form is merely illustrative'of'one combination and arrangement of parts calculated to attain the objects of the invention, pursuant to present preference, and'hence the detailed description of such form is not .to be taken as at all defining or limiting the invention itself: Thatis to say, the scope of protection contemplated is to be taken solely from the appended claims, interpreted as broadly as is consistent with the prior art, and with explanatory references to the specification only where a claim is ambiguous or to be impliedly limited be yond its express terms to avoid suchart in, order to save the validity of said claim.

In the accompanying drawings: i

Fig. 1 is a diagrammatic view illustrating one formof dependableyet readily adjust able and disengageable mount for the pulsator,together with one form of pulsator and circuit and possible relations of the actuating magnet and pulsator to a piano string,

the string in this figure being vertical as in an upright piano.

Fig. 2 is a similar view of aform of the de vice in its relation to a horizontal string, as in a grand piano.

Fig.3 is an enlarged side elevation with parts in section showing the mount and pulsator. V

Fig. 4 is a detail view in perspective showing a part of the pulsator and related elements.

Similar reference characters indicate similar parts throughout the several views of the drawings. In Fig. 1 a vertical piano string is indicated at 10, stretched over the bridge pieces 11 and 12. 13 indicates an electromagnet for vibrating the string and 14 indicates a pulsator for controlling the'magnet,

' said pulsator being located in a circuit with themagnet, which circuit includes a suitable source of energy 15 and a switch 16 operated by the piano key 17.

The piano-string hammer is conventionally indicated at H. The singing length of the string, as is well known, extends between the bridges 11 and 12. J

In the present case, one of the electrodes 18 of the pulsator is adjustably rigidly mechanically connected with the singinglength of the string, preferably near the upper bridge 11. Since the pulsator illustratively 7 shown is one having. substantially horizontal- 'ly opposed electrodes 18 and 19, with the latter preferably non-resonantlymounted by means of a non-vibratile auxiliary support, q

as, for example, a sheath 25 sleeved by a shell 23 of non-conducting material, the connection aforesaid maybe a blade or bar 21 directly carrying said shell and hence indirectly supporting both electrodes. The bar 21, which may be of metal, is provided with a .wed e-notch or fork 22 at its end for de pen ably yet readily adjustably engaging the string, and the fork 22 may haveconnected vto it another similar fork 22 which extends downwardly at right angles from the fork 22. There is a hinge 24 interposed between the fork 22 and the bar 21, so that the angle of the pulsator 14 with relation to the fork 22 may be varied, the parts being held in desired adjusted relation by means of screws 24: cooperating with the hinge Or any other means may be employed to hold the pulsator in desired angular relation with respect to its hinge pivot 24.

Means are provided for readily disconnecting all pulsators from all strings when ever desired, to adapt the piano for ordinary playing. F or example, a supporting bridge 26 may extend across the piano rockablc about its length, by suitable means, and can ryiug at its opposite ends trunnions or pivots indicated at 27. these trnnnions, of course, are rotatably mounted in suitable trunnion beds (not. shown) secured in place to some fixed part of: the piano. The supporting bar 21 for each pulsator is connected with the bridge by a. stip 30 which is fastened to the fork 22, and there is also a strip 31 which errtcnds from the briogc 26 and is pivoted as at 32 to a treadle mechanism or the like 3 It may be desirable to have the strip 30 of some other material than metal, that is, oi a material for instance like fibre, having little or u capacity for sympathetic-vibration liaison between the support and the bridge 26. will be evident that upon depression of the 'lreadlc 33 the ln'idge 22 will he rocked in an anti-clockwise direction, and the forks 22 of the several pulsators will be moved out of mechanical connection with the piano strings somewhat as shown in Fig. 3 of the drawings; and on rocking the bridge in the opposite di rection the forks 22 of all the supports 21 will wedgingly and securely engage with their appropriate strings.

The arrangement shown in Fig. 2 is in general similar to that already described, except that the dispo tion of the pulsator and magnet for each string will be changed in view of the horizontal disposition of the piano strings; and in this arrangement of parts the rig it-angled torlr 22 makes the contact with the strings instead oi the tori; 22.

If desired the piano strings may be divided into groups, as for instance 1721918 and l1l0lfJlG, each group under control of a member 26 and treadlc mechanism; or there may be a separate member 26 for each string.

The sostenuto effect is accomplished, in general, as set forth in. my U. 55. Patent No. 1,598,056, in which a string actuating m a gnct is controlled by a pulsator.

The subjectanatter of this present application is in part shown in my application for U. S. Patent Serial No. 178,206, filed March 25, 1927, and which last named application I propose to abandon in favor of: the present application.

Some of the features o'l this lIlYQZllLiOi'l are a plicable in my type of sostenuto device in which a pulsator is carried by a support, with a thread of sill: or the like stretched between pulsator and string. If the support is moved toward the string (in some such fashion as bar 21 is moved upon rocking of bridge 26) then the tension of the thread is relaxed, until at length all elfective operative connect-ion between pulsator and string is for the time being broken.

I claim:

.1. The combination of a vibratory string, a support provided with means for detachably securing the same to said string and carrying cooperating electrodes, a secondary support carrying the first support, and means for moving said supports relatively to detach the first supportfrom said string.

2. The combination of a vibratory string, a support provided with means for detachably securing the same to said string and carrying cooperating electrodes, a secondary support carrying the first support, and means for rocking one of said supports to detach the first support from said string.

3. The combination of a vibratory string, a support provided with means for detachably securing the same to said string and carrying cooperating electrodes, a secondary support carrying the first support, and means for moving said supports relatively to detachthc first support from said string, said first means including a wedge device.

4-. The combination of a vibratory string, a support provided with means for detachably securing the same to said string and carrying cooperating electrodes, a secondary support carrying the first support, and means for moving said supports relatively to detach the first support from said string, said first means having a fork including a wedge element.

5. The combination of a vibratory string, a support provided with means for detachably securing the same to said string and carrying cooperating electrodes, a secondary support carrying the first support, and means for moving said supports relatively to detach the first support from said string, said first means having ainotch to wedgingly embrace the string.

6. In anelectric sostenuto piano, a vibratory string, amagnet for vibrating the same, a pulsator incircuit with said magnet, means for detachably connecting said pulsator with the string, and means for releasing the pulsator from the string and including a support arranged to swing away from the string.

7.. In an electric sostenuto piano, vibratory strings, magnets for actuating the same, pulsators for said magnets connected with the strings, a. common support, and means includiug connections from said support to a plurality of the pulsators for simultaneously disconnecting said plurality of controllers.

8. The combination of a vibratory string, a support movable into and out of engagcment with said string and carrying cooperating electrodes,and means for moving said support relative to said string to engage and disengage the support and string.

9. The device set forth in claim 1, in which the first named means includeshingedly connected parts.

10. The device set forth in claim v1, in

which means are provided for accomplishing such movement.

13. A vibrating string, a magnet for actuating the string, apulsator controlling the magnet, the pulsator normally operatively connected to the string for effective actuation thereby, and means for breaking the operative connection between strlng and pulsator. V

In testimony whereof I aifix m signature.

SIMON OOPER. 

